OPTICAL DETECTION DEVICE OF A SELF-GUIDED FLYING MACHINE

TECHNICAL AREA

The present invention relates to the field of optical detection devices on board self-guided flying vehicles.

STATE OF THE PRIOR ART

A self-guided flying machine moves fully automatically thanks to an on-board guidance system whose function is to control the evolution of the trajectory of the self-guided flying machine in order to reach a goal. For this, such a guidance system comprises on the one hand a detector or detection device making it possible to detect the objective and in particular to determine the distance and the angular deviation with respect to this objective and on the other hand a processor of 'order whose role is to calculate the orders and transmit them to the control chain. Auto-guided flying machine detectors collect information from the environment, usually in the form of electromagnetic radiation. Depending on the detection means used, the radiation detected can be of different types such as radar waves or optical radiation in the visible or infrared. Imagers are also used in some cases.

Regarding the detection of optical radiation, an optical detection device of a self-guided flying machine generally comprises a window or porthole whose transparency allows the incident optical signal to pass, an optical system making it possible to direct and focus the optical signal and an optical detector or sensor connected to an information processing device.

Usually, optical sensing devices are placed in front of autoguided flying machines and more specifically on their dome. This position gives them a large field of view since no part of the craft obstructs the radiation emanating from the front and sides of the craft.

A problem with this position at the front of the autoguided flying machine is thermal heating of the optical detection device, linked to speed, or the high exposure to impact from the windows. In addition, this position is particularly sensitive to the attack load that can be built into a self-guided flying machine.

The use of hard materials such as sapphire to form the portholes improves the strength of these portholes. The transparency of materials in a

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However, the spectral band of interest is essential for a window and therefore strength is not the only criterion of choice. For example, sapphire cannot detect signals

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in certain infrared spectral bands, such as for example for wavelengths between 7 and 14 µm. It is then necessary to use another material, such as zinc sulphide, which is more fragile.

Some optical detection devices have sloped windows, which increases the incidence of attacks and reduces the impact of shocks. This inclination is nevertheless limited by aerodynamic and symmetry constraints on the dome of the self-guided flying machines.

Certain optical detection devices are also positioned on the airfoil of autoguided flying machines to limit damage.

It is desirable to provide a solution which makes it possible to limit the exposure to shocks and thermal heating of an optical detection device of a self-guided flying machine. It is further desirable to provide a solution which adapts to many detection spectral bands. It is also desirable to provide a solution which respects the aerodynamics of the autoguided flying machine.

DISCLOSURE OF THE INVENTION

The invention relates to an optical detection device comprising windows arranged in a collar on a self-guided flying machine.

An object of the present invention is to provide an optical detection device included in a self-guided flying machine, the self-guided flying machine being composed of a dome located at the head of the self-guided flying machine, of a propulsion device located at the rear of the self-guided flying machine and a body located between the dome and the propulsion device. The optical detection device comprises at least two windows arranged in a collar around the perimeter of the body of the self-guided flying machine.

Thus, it is possible to limit the exposure to shocks and thermal heating of an optical detection device of the self-guided flying machine while maintaining the symmetry of the self-guided flying machine.

According to a particular embodiment of the invention, the windows are inclined with respect to the propagation rate of the self-guided flying machine such that the angle formed by the normal to the surface of the windows and by the propagation rate of the The self-guided flying machine is between 10 ° and 60 °.

Thus, thermal warming effects and environmental impacts are minimized. ized. In addition, the aerodynamics of the self-guided flying machine is preserved.

According to a particular embodiment of the invention, the windows have a flat surface.

Thus, the manufacture of the optical detection device and the windows is carried out easily. In addition, the processing of the optical signal passing through the window is simplified.

According to a particular embodiment of the invention, the optical detection device further comprises, for at least part of the portholes, an optical system associated with each porthole, the optical system being placed behind the porthole and comprising a reflecting curved mirror. the optical signal to a plane mirror. The optical detection device also comprises at least one optical sensor onto which is directed at least one optical signal reflected by a curved mirror and a plane mirror, the optical sensor being connected to an information processing device.

Thus, the optical signal received through the windows can be processed and analyzed.

According to a particular embodiment of the invention, the optical detection device further comprises for each optical sensor a focusing system placed between the plane mirror and the optical sensor.

Thus, the focusing effected by the mirrors can be adjusted without the need to move the mirrors and focusing errors can be corrected.

According to a particular embodiment of the invention, all the windows of the optical detection device have identical optical characteristics. All the optical systems associated with the windows direct and focus the optical signals received through the windows on a single optical sensor and the optical sensor generates information representative of all the optical signals received through said windows.

Thus, it is possible to obtain an image of an object located in front of the autoguided flying machine.

According to a particular embodiment of the invention, the optical sensor is integrated into a filtering module comprising at least two spectral filters of different spectral bands. The filtering module extracts, from the optical signals received, an optical signal filtered in each of the spectral bands and generates information representative of each filtered optical signal.

Thus, it is possible to obtain, from windows of identical optical characteristics, several images of an object in different spectral bands.

According to a particular embodiment of the invention, at least one of the windows has optical characteristics that are different from the other windows. All the optical systems associated with windows with identical optical characteristics direct and focus the optical signals received through the windows on the same optical sensor and optical systems associated with windows with different optical characteristics direct and focus the optical signals received through the windows. windows of different optical characteristics on different optical sensors.

Thus, it is possible to obtain several images of the same object with different optical characteristics.

According to a particular embodiment of the invention, the windows with different optical characteristics have different spectral bands.

Thus, it is possible to obtain several images of the same object in different spectral bands. In addition, it is possible to adapt the windows using materials suitable for the detection spectral bands and which have the best impact resistance for each spectral band.

According to a particular embodiment of the invention, the optical detection device comprises for at least part of the portholes an imager associated with each porthole, the imager being placed so as to directly receive at least one optical signal passing through at least one porthole .

Thus, it is possible to process an optical signal received through a window independently and without requiring an optical system or mirrors.

BRIEF DESCRIPTION OF THE DRAWINGS

The characteristics of the invention mentioned above, as well as others, will emerge more clearly on reading the following description of at least one exemplary embodiment, said description being given in relation to the accompanying drawings, among which:

Fig. 1 schematically illustrates a self-guided flying machine in which the present invention is implemented;

Fig. 2a schematically illustrates in profile view an optical detection device comprising windows arranged in a collar on the body of a self-guided flying machine;

Fig. 2b schematically illustrates a front view of an optical detection device comprising windows arranged in a collar on the body of a self-guided flying machine;

Fig. 3 represents the inclination of each window with respect to the axis of propagation of the self-guided flying machine;

Fig.4 schematically illustrates a first example of the path of an optical signal in the optical detection device, in which the windows of the optical detection device arranged in a collar have identical characteristics;

Fig. 5 schematically illustrates a second example of the path of an optical signal in the optical detection device, in which the windows of the optical detection device arranged in a collar have different characteristics;

Fig. 6 schematically illustrates an optical detection device which comprises an imager behind a window; and

Fig. 7 schematically illustrates an optical detection device which comprises an imager oriented through the window towards the side of the autoguided flying machine.

DETAILED EXPOSURE OF EMBODIMENTS

The present invention consists of an optical detection device, the windows of which are placed in a collar on the body of a self-guided flying machine.

Fig. 1 schematically illustrates the self-guided flying machine 10 which comprises a dome 101 located at the head of the self-guided flying machine 10, a propulsion device 103 located at the rear of the machine and a body 102 located between the dome 101 and the propulsion device 103. The self-guided flying machine 10 also comprises an airfoil 104 which is made up of appendages which can be located at the rear of the self-guided flying machine 10 at the level of the propulsion device 103 or on the body 102. L The self-guided flying machine 10 further comprises an optical detection device 105, the windows of which are arranged, according to the present invention, in a collar on the body 102.

Fig. 2a shows, in profile view, the optical detection device 105 whose windows are arranged in a collar on the body 102 of the self-guided flying machine 10. The optical detection device 105 comprises several windows 20a, 20b, 20c and 20d corresponding to windows through which the optical signal from the outside is recovered. In the example of Fig. 2a, four portholes 20a to 20d are shown. The windows 20a to 20d are arranged in a collar on the surface of the self-guided flying machine 10. In other words, the windows 20a to 20d are positioned on the perimeter of the body 102 of the self-guided flying machine 10, thus forming a ring. around the autoguided flying machine 10.

The flanged arrangement of the windows 20 maintains the symmetry of the self-guided flying machine 10 and its aerodynamics. The arrangement of the portholes 20 on the body 102 makes it possible to minimize the effects of thermal heating or impacts linked to the environment such as rain erosion.

The windows can be identical but also differ from each other by the nature of their material. For example, one of the windows can be made of sapphire, which allows the recovery of optical signals in the spectral band of 0.3 µm to 5 µm while another window can be made of zinc sulphide, which is more fragile than. sapphire but allowing the recovery of optical signals in a spectral band of higher wavelengths, up to 15 µm. The windows can also differ from each other in their dimensions and the curvature of their surface. The windows can thus have a flat outer surface, which allows easier manufacture and simplifies the processing of an optical signal received through the window.

Fig. 2b shows a front view of the optical detection device 105, the windows of which are arranged in a collar. The optical signal is recovered in a band or an annular zone 30 on the periphery of the autoguided flying machine 10 delimited by the outer perimeter 31 of the part of the autoguided flying machine 10 located at the front of the detection device. optical 105 on the one hand and the outer perimeter 32 of the part of the self-guided flying machine 10 located at the rear of the optical detection device 105 on the other hand. The windows 20a to 20f are located in the annular zone 30 and are distributed all around the machine. They are arranged regularly or with variable spacing. In the example of Fig. 2b, six portholes are shown. Of course, a greater or lesser number of windows can be used by the present invention.

Fig. 3 represents the inclination of each window 20 relative to the axis of propagation of the self-guided flying machine 10.

Each porthole 20 is inclined relative to the surface of the body 102 of the autoguided flying machine 10 so that an optical signal from the front of the autoguided flying machine 10 can be retrieved.

The angle a between the axis of propagation 311 of the self-guided flying machine 10 and the normal 312 to the surface of the window 20 is between 10 ° and 60 °, preferably between 20 ° and 40 °.

Fig. 4 schematically illustrates a first example of the optical signal path in the optical detection device 105, in which the windows of the optical detection device 10

CLAIMS

1. Optical detection device included in a self-guided flying machine, the self-guided flying machine consisting of a dome located at the head of the self-guided flying machine, a propulsion device located at the rear of the flying machine self-guided and of a body located between the dome and the propulsion device, characterized in that the optical detection device (105) comprises at least two windows (20a, 20b, 20c, 20d) arranged in a collar around the periphery of the body of the self-guided flying machine, and in that it also comprises, for at least part of the windows:

an optical system associated with each window, the optical system being placed behind said window and comprising a curved mirror reflecting the optical signal towards a plane mirror,

- at least one optical sensor onto which is directed at least one optical signal reflected by a curved mirror and a plane mirror, the optical sensor being connected to an information processing device.

2. Optical detection device according to claim 1, characterized in that the windows are inclined relative to the axis of propagation of the self-guided flying machine such that the angle formed by the normal to the surface of the windows and by the axis of propagation of the self-guided flying machine is between 10 ° and 60 °.

3. Optical detection device according to one of claims 1 and 2, characterized in that the windows have a flat surface.

4. Optical detection device according to one of claims 1 to 3, characterized in that the optical detection device further comprises for each optical sensor a focusing system placed between the plane mirror and the optical sensor.

5. Optical detection device according to one of claims 1 to 4, characterized in that all the windows have identical optical characteristics, all the optical systems associated with the windows direct and focus the optical signals received through the windows on the same. optical sensor and the optical sensor generates information representative of all the optical signals received through the windows.

6. Optical detection device according to claim 5, characterized in that the optical sensor is integrated in a filtering module comprising at least two spectral filters of different spectral bands, the filtering module extracts, from the optical signals received, a optical signal filtered in each of the spectral bands and generates information representative of each filtered optical signal.

7. Optical detection device according to any one of claims 1 to 4, characterized in that at least one of the windows has optical characteristics different from the other windows, in that all the optical systems associated with windows of optical characteristics identical direct and focus the optical signals received through the windows on the same optical sensor and in that optical systems associated with windows of different optical characteristics direct and focus the optical signals received through the windows of different optical characteristics on sensors different optics.

8. An optical detection device according to claim 7, characterized in that the windows of different optical characteristics have different spectral bands.

9. Self-guided flying machine, characterized in that it comprises an optical detection device according to any one of claims 1 to 8.